Device for fixing spring winder means

ABSTRACT

The device firmly secures a spring winder means to a spring winding stem by means of a coil spring intimately fitted over the spring winder means and the spring winding stem threadably connected together. The convolutions of the coil spring are directed in the same direction as the threads formed in the spring winder means and spring winding stem for threadable connection, so that the coil spring is tightened if the spring winder means is turned in a direction in which it is threadably disconnected from the spring winding stem. Thus, the spring winder means is firmly secured to the spring winding shaft through the coil spring and prevented from being dislodged therefrom.

ited States Patent 2 [191 Suzuki 1 Sept. 25, 11973 [54] 325: FOR FIXINGSPRING WINDER FOREIGN PATENTS OR APPLICATIONS 1,067,245 1/1954 France192/81 C [75] Inventor: lkuo Suzuki, Okaya-shi,

Naganmken Japan Primary ExaminerAndrew V Kundrat [73] Assignee:Kabushiki Kaisha Sankyo Seiki Att0rney.l0hn J McGlew et al.

Seisakusho, Nagano-ken, Japan [22] Filed: June 1, 1972 [57] ABSTRACT[21] Appl. No.: 258,541 The device firmly secures a spring winder meansto a spring winding stem by means of a coil spring intimately fittedover the spring winder means and the [30] Forelgn Apphcanon Priority Damspring winding stem threadably connected together. June 8, 1971 Japan46/47562 The Convolutions f th oil spring are directed in the samedirection as the threads formed in the spring 52] 92/82 403/341 403/377winder means and spring winding stem for threadable [51] lint. C1. lFl6dl/Oll connection, so h h il spring is tightened if the Fleld Of Search86, p g winder means is turned in a direction in 92/41 12 Isl/.14 285/32- itis threadably disconnected from the spring winding 32 24/123 77 27 CT stem. Thus, the spring winder means is firmly secured to thespring winding shaft through the coil spring and [56] References cuedprevented from being dislodged therefrom.

UNITED STATES PATENTS 3,662,867 5/1972 Kinzbach 192 45 6 Clam, 3 DrawmgFgures DEVICE FOR FIXING SPRING WINDER MEANS Background of the InventionThis invention relates to a device for fixing a winder means for springsor the like.

Generally, a key for winding a spring, or other means for performing thesame function as the key are detachably connected, as by threading, to aspring winding stem attached to the spring, so that the key can freelybe connected to or disconnected from the spring winding stem.

When the spring winder means is detachable from the spring winding stem,it is likely to be lost or misplaced. When such detachable spring windermeans is used with a clockworktoy for children, there is the hazard of asmall child putting it in the mouth, while play ing, and swallowing it.

It is desirable therefore that the spring winder means be constructedsuch that it cannot readily be disconnected from the spring winding stemonce it is conpair and disassembling. Loosening of the coil springshould require a considerably high force, so that the winder means isprevented from being inadvertently dislodged or removed by a child.

Other and additional objects as well as features and advantages of theinvention will become evident from the description set forth hereinafterwhen considered in conjunction with the accompanying drawings.

Brief Description of the Drawings FIG. 1 is a plan view, with certainparts being broken away, of the device for fixing spring winder meanscomprising one embodiment of this invention, showing the spring windermeans having the coil spring mounted over it being juxtaposed to thespring winding stem;

FIG. 2 is a plan view, with certain parts being broken I away, of thedevice according to this invention, showspring winder means and thespring winding stem may be crushed by crimping it with pliers, or theformer may be joined by soldering to the latter. If the spring windermeans were firmly secured to the spring winding stern of a toy in thisway, it would be impossible to disconnect them till the toy is brokenand discarded. Thus, when it is desired to repair the toy, it would beimpossible to disassemble it into its component parts.

Summary of the Invention This invention has as its object the provisionof a device for fixing spring windertmeans comprising a spring windingstem having a threaded portion, a spring winder means having a threadedportion adapted to be threadably connected to the threaded portion ofthe spring winding stem, and a coil spring adapted to be fittedintimately over the spring winding stem and the spring winder means,threadably connected together, the coil spring comprising convolutionsarranged in a direction which is the same as the direction in which thethreads formed on the spring winding stem and the spring winder meansfor threadably connecting them together are wound, so that the springwinder means threadably connected to the spring winding stem can befirmly secured thereto by means of the soil spring and cannot readily bedisconnected therefrom by turning the spring winder means in anydirection once it is fixed to the spring winding shaft.

The device according to this invention is very simple in constructionand yet positive in performing the operation of firmly securing thespring winder means to the spring winding stem and preventing it frombeing disconnected. The coil spring mounted between the spring windermeans and the spring winding stem ensures that the winder means is notdisconnected from the winding stem once the former is threadablyconnected to the latter.

According to this invention, the spring winder means is not permanentlyconnected to the spring winding stem, but theformer can be disconnectedfrom the latter when desired. That is, if the spring winder means isunscrewed after the coil spring is loosened, the spring winder means canbe readily disconnected from the spring winding stem. This arrangementfacilitates reing the spring winder means having the coil spring mountedover it being threadably connected to the spring winding stem; and

FIG. 3 is a fragmentary plan view, on an enlarged scale, of FIG. 2. I

Description of a Preferred Embodiment The invention will now bedescribed with reference to an embodiment in which the spring windermeans is a key provided with an internal threaded portion and the springwinding stem is provided with an external threaded portion. It is to beunderstood that the invention is not limited to this embodiment and thatan internal threaded portion may be provided in the spring winding stemand an external threaded portion may be provided in the spring windermeans. The spring winding stem may be a shaft having one end to which aspring is attached, or may be a spring shaft itself.

In FIG. I, a spring winding stem ll having a spring 4 attached to oneend portion threrof is supported by a frame 3 suchas of a toy, and theother end portion of spring winding stem 1 is provided with an externalthreaded portion 2.

On the other hand, a spring winder means or key 5 adapted to beconnected'to spring winding stem 11 is provided at a forward end portionthereof with an internal threaded portion 6 adapted to threadably engagethe external threaded portion 2 of the spring winding stem 1.

The key 5 is formed on the outer circumferential surface thereof with anoffset portion 9 to provide a minor diameter portion 7 at the endportion of key 5 which has an outer diameter substantially the same asthe outer diameter of spring winding stem 1. A coil spring 8, havingconvolutions directed in the same direction as the thread of thethreaded portion on the key S is lightly force fitted over the minordiameter portion 7 of key 5 at one end portion thereof, and then the key5 is threadably connected to the spring winding stem 1 so that the otherend portion of coil spring 8 is lightly force fitted over the outercircumferential surface of spring winding stem 1 as shown in FIG. 2.Preferably, the coil spring 8 has an inner diameter which is equal to orsmaller than the outer diameter of the minor diameter portion of key 5.The coil spring 8 may be constructed such that its inner peripheralsurface partly engages winding stem 1 and key 5.

If one tries to turn the key 5 in the direction of an arrow as shown inFIG. 3 in an effort to disconnect the key 5 from the spring winding stemI by unscrewing after the coil spring 8 is force fitted over thethreadably connected key and stem 1, the key 5 and stem 1 will be lockedby the coil spring 8 since the frictional force imparted to the coilspring 8 when it is force fitted over the minor diameter portion of key5 acts on the coil spring 8 to force it tightly over the stem 1 byvirtue of the arrangement in which the convolutions of coil spring 8 aredirected in the same direction as the thread formed on the key S. It isthus impossible to disconnect the key 5 from the winding stem 1 byunscrewing. Also,

the frictional force imparted to the coil spring 8 when it is forcefitted over the spring winding stem 1 in threadably connecting the key 5to the stem 1 acts to loosen the coil spring 8, thereby enabling the key5 and stem 1 to be maintained in threadable connection.

The coil spring 8 is precluded from axial movement by abutment againstthe offset portion 9 and against the frame 3 to which the spring windingstem 1 is connected, the offset portion 9 having a height which isgreater than or equal to the diameter a of a wire constituting thespring Thus, end portions of the coil spring are not exposed and thehazards of the hands of a child being injured by them are precluded. Itis to be understood that the offset portion can be provided on the outercircumferential surface of the spring winding shaft 1, not on the outercircumferential surface of the key 5 as aforementioned.

According to this invention, the portion of the coil spring 8 whichextends outwardly beyond the end of the minor diameter portion 7 of key5 over which the coil spring 8 is force fitted has a length b which issmaller than the length of the external threaded portion 2 of the springwinding stem 1. By this arrangement, the force fitting of the coilspring 8 over the spring winding stem 1 can be initiated while thespring winding stem 1 is still in the process of being screwed into thekey 5. This expands the coil spring 8 and thereby facilitates thescrewing of the spring winding stem 1 into the key 5.

When the inner diameter of coil spring 8 is much smaller than the outerdiameter of spring winding stem 1, the force fitting of coil spring 8over the spring winding stem 1 will be facilitated if the portion of thecoil spring 8 disposed on the side of spring winding stem 1 is expandedto have a greater inner diameter or if the end of the stem 1 from whichthe external threaded portion 2 extends is cut aslant to provide ashoulder la therein.

What I claim is:

1. A device for fixing spring winder means comprising a spring windingstern formed with a threaded portion, a spring winder means formed witha threaded portion and adapted to be threadably connected to said springwinding stem, one of said threaded portions being a male threaded studand the other of said threaded portions being a female threaded socketportion for receiving said threaded stud; and a cylindrical coil springintimately fitted around non-threaded portions of said spring windingstern and said spring winder means when said stem and said winder meansare threadably connected to each other, said coil spring being wound ina direction which is the same as the direction in which the threads ofthe threaded portions, formed on the spring winding stem and the springwinder means extend for threadably connecting them together.

2. A device for fixing spring winder means as set forth in claim 1wherein said spring winder means is formed with a minor diameter portionover which said coil spring is adapted to be fitted, said minor diameterportion of said spring winder means having an outer diameter which issubstantially the same as the outer diameter of a portion of said springwinding stern which has no thread thereon, said coil spring having aninner diameter which is equal to or smaller than the outer diameter ofsaid minor diameter portion of said spring winder means.

3. A device for fixing spring winder means as set forth in claim 1wherein at least one of said spring winder means and said spring windingstem is formed with an offset portion of a height greater than thediameter of a wire constituting said coil spring.

4. A device for fixing spring winder means as set forth in claim 1wherein the threaded portion of said spring winder means is an externalthreaded portion and the threaded portion of said spring winding stem isan internal threaded portion.

5. A device for fixing spring winder means as set forth in claim 1wherein the threaded portion of said spring winder means is an internalthreaded portion and the threaded portion of said spring winding stem isan external threaded portion.

6. A device for fixing spring winder means as set forth in claim 5,wherein a portion of said coil spring extending outwardly from the endof said minor diameter portion of said spring winder means, over whichsaid coil spring is fitted, has a length which is smaller than thelength of said external threaded portion of said spring winding stem.

1. A device for fixing spring winder means comprising a spring windingstem formed with a threaded portion, a spring winder means formed with athreaded portion and adapted to be threadably connected to said springwinding stem, one of said threaded portions being a male threaded studand the other of said threaded portions being a female threaded socketportion for receiving said threaded stud; and a cylindrical coil springintimately fitted around non-threaded portions of said spring windingstem and said spring winder means when said stem and said winder meansare threadably connected to each other, said coil spring being wound ina direction which is the same as the direction in which the threads ofthe threaded portions, formed on the spring winding stem and the springwinder means extend for threadably connecting them together.
 2. A devicefor fixing spring winder means as set forth in claim 1 wherein saidspring winder means is formed with a minor diameter portion over whichsaid coil spring is adapted to be fitted, said minor diameter portion ofsaid spring winder means having an outer diameter which is substantiallythe same as the outer diameter of a portion of said spring winding stemwhich has no thread thereon, said coil spring having an inner diameterwhich is equal to or smaller than the outer diameter of said minordiameter portion of said spring winder means.
 3. A device for fixingspring winder means as set forth in claim 1 wherein at least one of saidspring winder means and said spring winding stem is formed with anoffset portion of a height greater than the diameter of a wireconstituting said coil spring.
 4. A device for fixing spring windermeans as set forth in claim 1 wherein tHe threaded portion of saidspring winder means is an external threaded portion and the threadedportion of said spring winding stem is an internal threaded portion. 5.A device for fixing spring winder means as set forth in claim 1 whereinthe threaded portion of said spring winder means is an internal threadedportion and the threaded portion of said spring winding stem is anexternal threaded portion.
 6. A device for fixing spring winder means asset forth in claim 5, wherein a portion of said coil spring extendingoutwardly from the end of said minor diameter portion of said springwinder means, over which said coil spring is fitted, has a length whichis smaller than the length of said external threaded portion of saidspring winding stem.